Arcam rPAC Best Performance Review, Specs and Price

A computer manufacturer, even one with a strong history in audio - yes I'm talking to you Apple - is primarily concerned with computing performance and usability, not with the audio quality from the headphone socket. As such, components such as the DAC and amplification circuitry will be far from ideal if audio quality is important to you. The Arcam rPAC is a compact external DAC and headphone amplifier that will pump pure, clean and, quite simply, beautiful music to your ears. But what's amazing about the rPAC is that you can pick one up for under £150!

Of course there are ways to bypass the internal audio circuitry in a computer, with higher-end soundcards and media-based notebooks sporting digital audio outputs in either optical or coaxial flavours. However, it's a common misconception that a digital audio signal is as good as perfect, with S/PDIF solutions subject to jitter. The introduction of asynchronous USB has all-but eliminated digital jitter, by taking timing control away from the computer. An external DAC employing asynchronous USB will essentially tell the computer when to send data, and thus remove the issue of out-of-phase clocks that cause jitter.

So, it is possible to extract a very clean audio signal from your computer by using an external DAC connected via asynchronous USB. Unfortunately such external DACs have traditionally been very expensive, that is, until now. Before I get into the specifics, let me make one thing clear - I love the rPAC. In all honesty, I don't ever want this little black box to leave my desk. But when the day does come to return this review sample, I'll be buying an rPAC for myself.

What's so special about the rPAC? Well, while there's a host of other external DACs with integrated headphone amps on the market, most of them are trying to be all things to all men. Most will be battery operated so you can use them on the move, many will include optical digital inputs for versatility, and very few of them will sport an asynchronous USB connection - not at this price point anyway.

Arcam rPAC - Specifications & Performance :

Arcam rPAC Specifications

At the heart of the rPAC is a TI Burr-Brown PCM5102 DAC chipset, the same one used to such good effect in the drDock. Arcam throws out numerous stats which certainly look good on paper (see below), but the highlights are the support for 24bit depth, sample rates up to 96kHz, a frequency response of 10Hz to 20kHz and headphone output power up to 138mW - enough to power the vast majority of headphones without issue.

On top of this is RF suppression which combats the interference created by high frequency radio bands inside a computer from the likes of the power cables, ports and the internal microphone. The cherry on the top is the inclusion of asynchronous USB which reduces the noise and jitter associated with USB music sources. This problem occurs due to the computer being responsible for the timing in the playback. Asynchronous technology bypasses that by using its own precision clock circuits to control the timing inside the DAC.

Technical Specification :

DAC Chipset TI Burr-Brown PCM5102

Input USB (Asynchronous)

Frequency response 10Hz - 20khz,±0.1dB

Total Harmonic Distortion + Noise 0.002%

Signal-to-noise ratio (A-Weighted) 106dB (24-bit)

Line output level 2.15Vrms / 2x RCA / Photo sockets (gold plated)

Supported sample rates 44.1kHz,48kHz,88.2kHz,96kHz

Bit depth 16-bit and 24-bit

Heandphone output power 138mW

Performance

Upgrading from a typical onboard sound card to the rPAC results in immediately obvious improvement across the board. Like the drDock, the rPAC brings greater clarity, depth and deeper, more resonant bass. Moreover, the general background hiss and audiological grime that poor quality computer audio is covered in is essentially eliminated. A crude analogy would like listening to music from behind a closed window then opening it.

If we can level a criticism it is that the treble does occasionally sound a little shrill, but we found this only on tracks with particularly wild sonic make-ups such as A Lily's 'Lights Shone Brighter, My Delicate Sun Is My Sparklin' Sun' which is hardly representative of the vast majority of music!

It should also be noted that the rPAC isn't only at home with music. Any audio emanating from your computer will be given the once over, so it will enhance everything from streaming video services like Sky Go, and BBC iPlayer particularly when watching good quality content like films on the former and nature documentaries on the latter (not to mention Later With Jools Holland). Internet Radio also receives a welcome and much needed boost whether it is music focused or simply conversation based like BBC Radio 5 Live. In short we found no situation where our computer's audio output did not enjoy substantial benefit.

That's not to say that the rPAC doesn't deliver with more punchy, bass heavy source material. D'Angelo's Brown Sugar pours forth from the rPAC like honey. The leading bass line surrounds you like a warm blanket, while the snare cracks like a whip over the top. In fact, the rPAC made me remember just how superb the production is on this track, and the album as a whole.

Switching genre to something more rock focussed caused no problems for the rPAC either, with Temple of the Dog's self titled album coming through with a loud, full-throttled presence. Despite Chris Cornell's vocals sitting way up front in the mix, there's a superb cohesion to the arrangements highlighted by the rPAC, especially on the opening track, Say Hello to Heaven.

I could go on, but rest assured that the rPAC will transform whatever you pump through it, regardless of genre. It's like some arcane, black magic box that performs mysterious miracles - you might not know how it does it, but you'll be very pleased that it does.